1. Field of the Invention
The present invention relates to a treatment solution supply apparatus and a treatment solution supply method.
2. Description of the Related Art
In a photolithography process, for example, in semiconductor device fabrication processes, resist coating treatment for applying a resist solution on a surface of a substrate, for example, a semiconductor wafer (hereinafter referred to as a xe2x80x98waferxe2x80x99), to form a resist film, exposure processing for exposing the wafer in a pattern, developing treatment for developing the wafer after being exposed in the pattern, and so on are performed to form a predetermined circuit pattern on the wafer.
The above resist coating treatment is usually performed in a resist coating unit. This resist coating unit includes a spin chuck 120 for mounting the wafer thereon and rotating the wafer, a plurality of resist solution supply nozzles 121 for supplying the resist solution to the wafer from a position above a center of the wafer, and a carrier 122 for holding and carrying the resist solution supply nozzles 121, when the resist solution is applied, for example, as shown in FIG. 15.
The carrier 122 includes a nozzle holder 123 for holding the resist solution supply nozzles 121 and an arm portion 124 to which the nozzle holder 123 is attached. The arm portion 124 is structured to be movable along a rail 125 which extends in an X-direction beside the spin chuck 120. The arm portion 124 is also movable in a Z-direction. The nozzle holder 123 is fixed to the arm portion 124 in a predetermined position so that the nozzle holder 123 is positioned above the center of the wafer W when the arm portion 124 moves to be positioned above the center of the wafer.
Before being held by the nozzle holder 123, the resist solution supply nozzles 121 are kept on stand-by in a nozzle box 126 which is disposed beside the spin chuck 120. The nozzle box 126 is movable in a Y-direction. Then, when one of the resist solution supply nozzles 121 held by the nozzle holder 123 is to be replaced by another one of the resist solution supply nozzles 121, the nozzle box 126 moves in the Y-direction to position said another one of the resist solution supply nozzle 121, which is to be held next, under the nozzle holder 123.
Therefore, in the above-described resist coating unit, the resist coating treatment is performed in a manner in which the arm portion 124 moves in the X and Z-directions so that the nozzle holder 123 holds the resist solution supply nozzle 121 which is kept on stand-by in the nozzle box 126 and the resist solution supply nozzle 121 is caused to move to a position above the center of the wafer and thereafter, the resist solution is supplied to the rotated wafer from the resist solution supply nozzle 121.
However, the position of the nozzle holder 123 cannot be finely adjusted in the Y-direction even when the resist solution discharged from the resist solution supply nozzle 121 which is held by the nozzle holder 123 is not accurately supplied to the center of the wafer since the nozzle holder 123 is fixed to the arm portion 124. Thus, when the resist solution cannot be supplied to the center of the wafer due to the inability of finely adjusting the position of the nozzle holder 123, the supply amount of the resist solution needs to be increased so much more in order to form a uniform resist film on the wafer, which results in an increase in cost.
The present invention is made in consideration of the above-described aspects and provides a treatment solution supply apparatus and a treatment solution supply method in which the adjustment of the position of a treatment solution supply nozzle is facilitated so that a treatment solution such as a resist solution discharged from a treatment solution supply nozzle is supplied to an accurate position on a substrate such as a wafer.
A treatment solution supply apparatus according to the present invention is a treatment solution supply apparatus for supplying a treatment solution onto a substrate which is disposed in a predetermined processing position on a mounting portion, comprising: a treatment solution supply nozzle for supplying the treatment solution onto the substrate; and a nozzle holder for releasably holding the treatment solution supply nozzle, wherein the treatment solution supply nozzle is disposed in a predetermined stand-by position and the nozzle holder is movable in three dimensions.
The nozzle holder is structured to be movable in three dimensions as described above so that the position of the treatment solution supply nozzle can be finely adjusted and thereby, the treatment solution can be accurately supplied to an appropriate position on the substrate. Consequently, the treatment solution can be supplied accurately to the center of the substrate, for example, when the treatment solution is supplied onto the rotated substrate so that the amount of the treatment solution used can be decreased so much more. Furthermore, when what is called xe2x80x9cposition calculationxe2x80x9d, which means to specify, for example, the center position of the substrate and the position where the plural treatment solution supply nozzles are kept on stand-by, and which is performed before the treatment solution is supplied onto the substrate, is performed, the movement of the nozzle holder in three dimensions also makes it possible to perform a more accurate location without manned mechanical adjustment.
When the plural treatment supply nozzles are provided, the plural treatment supply nozzles are disposed outside the substrate which is in the processing position and may be arranged in an arc shape with the center of the substrate being the center of the arc or may be linearly arranged. In this case, it is appropriate that treatment solution tubes connected to the respective treatment solution supply nozzles are disposed to radially extend in an outward direction from the respective treatment solution supply nozzles with the center of the substrate which is disposed in the predetermined processing position being the center of the radiation. This arrangement is appropriate since it can appropriately prevent the tubes from contacting each other.
In the treatment solution supply apparatus according to the present invention, a hole formed in the center of the processing position on the mounting portion, a light-emitting part for emitting a light through the hole in an upward direction, a light-receiving part, which is provided in the nozzle holder, for receiving the emitted light, and a specifying device for specifying, based on a position where the light-receiving part receives the light from the light-emitting part, the position of the center of the substrate disposed in the processing position may further be added. In this case, a laser displacement gauge may be provided in the nozzle holder side to detect the hole, instead of providing the light-emitting part in the hole.
Moreover, a specifying mechanism for specifying, based on the position of the nozzle holder when the nozzle holder holds an optional one of the treatment solution supply nozzles which is positioned in the stand-by position, coordinates of the stand-by position of the optional treatment solution supply nozzle in a coordinate system including the processing position may be added.
For more direct detection, an image pickup device for monitoring the substrate disposed in the processing position may be used for monitoring.
A treatment solution supply method according to the present invention utilized a treatment solution supply apparatus comprising: a mounting portion for mounting the substrate thereon; a plurality of treatment solution supply nozzles for supplying the treatment solution on the substrate; and a nozzle holder movable in three dimensions for holding the treatment solution supply nozzles, in which the treatment solution supply nozzles are disposed outside the substrate which is on the mounting portion and are arranged in a predetermined stand-by position in an arc shape with the center of the substrate being the center of the arc. The treatment solution supply method according to the present invention comprises the steps of: holding the treatment solution supply nozzle kept in the stand-by position, with the nozzle holder moving thereto; and carrying by the nozzle holder the treatment solution supply nozzle linearly from the stand-by position to a position above the center of the substrate on the mounting portion.
A treatment solution supply method according to the present invention is a treatment solution supply method for supplying a treatment solution onto a substrate, wherein utilized is a treatment solution supply apparatus comprising: a mounting portion for mounting the substrate thereon; a treatment solution supply nozzle for supplying a treatment solution on the substrate; and a nozzle holder movable in three dimensions for releasably holding the treatment solution supply nozzle, and utilized is a position detector having a shape same as that of the substrate. The position detector includes two light-emitting parts for linearly emitting lights in a manner in which the lights are emitted from different positions and pass through a center, namely, a center of the position detector having the shape same as that of the substrate, and two light-receiving parts for receiving the emitted lights from the light-emitting parts.
The treatment solution supply method according to the present invention comprises the steps of: disposing the position detector in a predetermined processing position on the mounting portion before the treatment solution is supplied onto the substrate; and moving the treatment solution supply nozzle held by the nozzle holder to the center of the position detector to position the treatment solution supply nozzle in a position where the treatment solution supply nozzle blocks the two linear lights synchronously.
According to the treatment solution supply method of the present invention, the nozzle holder is movable in three dimensions, which makes it possible to finely adjust the position of the treatment solution supply nozzle to accurately supply the treatment solution to an appropriate position on the substrate. Furthermore, the treatment solution supply nozzle is carried linearly, which makes it possible to move the treatment solution supply nozzle quickly to a predetermined position.
Moreover, according to the treatment solution supply method, the position detector is utilized so that the treatment solution supply nozzle can be positioned in the position where the treatment solution supply nozzle blocks the two linear lights synchronously, which makes it possible to position the treatment solution supply nozzle in the xe2x80x9ccenter positionxe2x80x9d quickly and accurately.